- ID:
- ivo://CDS.VizieR/J/ApJ/513/34
- Title:
- HDF photometric redshifts catalog
- Short Name:
- J/ApJ/513/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the newly available infrared images of the Hubble Deep Field in the J, H, and K bands and an optimal photometric method, we have refined a technique to estimate the redshifts of 1067 galaxies. A detailed comparison of our results with the spectroscopic redshifts in those cases where the latter are available shows that this technique gives very good results for bright enough objects [AB(814nm)<26.0]. From a study of the distribution of residuals [{Delta}z_rms_/(1+z)~0.1 at all redshifts], we conclude that the observed errors are mainly due to cosmic variance. This very important result allows for the assessment of errors in quantities to be directly or indirectly measured from the catalog. We present some of the statistical properties of the ensemble of galaxies in the catalog, and we finish by presenting a list of bright high-redshift (z~5) candidates extracted from our catalog together with recent spectroscopic redshift determinations confirming that two of them are at z=5.34 and z=5.60.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/655/51
- Title:
- HDFS IRAC observations of 2<z<3.5 galaxies
- Short Name:
- J/ApJ/655/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze very deep HST, VLT, and Spitzer photometry of galaxies at 2<z<3.5 in the Hubble Deep Field-South. The sample is selected from the deepest public K-band imaging currently available. We show that the rest-frame U-V versus V-J color-color diagram is a powerful diagnostic of the stellar populations of distant galaxies. Galaxies with red rest-frame U-V colors are generally red in rest-frame V-J as well. However, at a given U-V color a range in V-J colors exists, and we show that this allows us to distinguish young, dusty galaxies from old, passively evolving galaxies. We quantify the effects of IRAC photometry on estimates of masses, ages, and the dust content of z>2 galaxies.
- ID:
- ivo://CDS.VizieR/J/A+AS/145/111
- Title:
- HDF-South catalogue of galaxies
- Short Name:
- J/A+AS/145/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of galaxies in the HDF-S, created using the public version 1 images of the WFPC2 data. We created a catalogue with 4 pass-band (I(814), V(606), B(450), U(300). In V(606), B(450), U(300) and I(814), for each galaxy the catalogue gives photometric parameters. For the I(814), we estimated also the colours and for I(814)<26, the petrosian radius, the mean surface brightness within the petrosian radius, light concentration indexes, that is C_eta_ and C_abr_, and the asymmetry index as computed by Abraham software.
- ID:
- ivo://CDS.VizieR/J/AJ/122/2205
- Title:
- HDF-South K photometric redshift catalog
- Short Name:
- J/AJ/122/2205
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from the Faint Infra-Red Extragalactic Survey of the Hubble Deep Field South (HDF-S). Using a combination of deep near-infrared (NIR) data obtained with the Infrared Spectrograph and Array Camera at the VLT and the WFPC2 Hubble Space Telescope data, we construct a K-band-selected sample which is 50% and 90% complete for K_s,AB_<=23.5 and K_s,AB_<=22.0, respectively, where the magnitudes are measured over a 2.0" diameter aperture. For z<=3, our selection by the K-band flux chooses galaxies based on wavelengths redder than the rest-frame V band, and so selects them in a way that is less dependent on their current star formation rates than selection in the rest-frame UV.
- ID:
- ivo://CDS.VizieR/J/ApJ/538/493
- Title:
- HDF-South NICMOS field
- Short Name:
- J/ApJ/538/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of photometry and photometric redshifts of 335 faint objects in the Hubble Deep Field South (HDF-S) near-infrared camera and multiobject spectrograph (NICMOS) field. The analysis is based on (1) infrared images obtained with the Hubble Space Telescope (HST) using the NICMOS with the F110W, F160W, and F222M filters; (2) an optical image obtained with HST using the Space Telescope Imaging Spectrograph with no filter; and (3) optical images obtained with the European Southern Observatory Very Large Telescope with U, B, V, R, and I filters. The primary utility of the catalog of photometric redshifts is as a survey of faint galaxies detected in the NICMOS F160W and F222M images. The sensitivity of the survey varies significantly with position, reaching a limiting depth of AB(1.6{mu}m)~28.7 and covering 1.01arcmin^2^ to AB(1.6{mu}m)=27 and 1.05arcmin^2^ to AB(1.6{mu}m)=26.5. The catalog of photometric redshifts identifies 21 galaxies (or 6% of the total) of redshift z>5, eight galaxies (or 2% of the total) of redshift z>10, and 11 galaxies (or 3% of the total) of best-fit spectral type E/S0, of which five galaxies (or 1% of the total) are of redshift z>1.
- ID:
- ivo://CDS.VizieR/J/A+A/626/A95
- Title:
- HD160305 images with SPHERE
- Short Name:
- J/A+A/626/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Direct imaging of debris disks gives important information about their nature, their global morphology and allows to identify specific structures possibly in connection with the presence of gravitational perturbers. It is the most straightforward technique to observe planetary systems as a whole. We present the first resolved images of the debris disk around the young F-type star HD 160305, detected in scattered light using the VLT/SPHERE instrument in the near infrared. We used a post-processing method based on Angular Differential Imaging and synthetic images of debris disks produced with a disk modeling code (GRaTer) to constrain the main characteristics of the disk around HD160305. All of the point sources in the field of the IRDIS camera were analyzed with an astrometric tool to determine whether they are bound objects or background stars. We detect a very inclined (~82{deg}) ring-like debris disk located at a stellocentric distance of about 86au (deprojected width ~27au). The disk displays a brightness asymmetry between the two sides of the major axis, as can be expected from scattering properties of dust grains. We derive an anisotropic scattering factor g>0.5. A second right-left asymmetry is also observed with respect to the minor axis. We measure a surface brightness ratio of 0.73+/-0.18 between the bright and the faint sides. Because of the low signal-to-noise ratio (S/N) of the images we cannot easily discriminate between several possible explanations for this left-right asymmetry, such as perturbations by an unseen planet, the aftermath of the breakup of a massive planetesimal, or the pericenter glow effect due to an eccentric ring. Two epochs of observations allow us to reject the companionship hypothesis for the 15 point sources present in the field.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1910
- Title:
- HD 131861 radial velocities and VRI light curves
- Short Name:
- J/AJ/132/1910
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our red-wavelength spectroscopic observations of HD 131861, a previously known single-line multiple system, span 20 years. Now lines of two components, the short-period F5 V primary and G8 V secondary, have been detected. The inner orbit is circular with a period of 3.5507439-days, while the outer orbit of the system has a period of 1642 days or 4.496-yr and a relatively low eccentricity of 0.10. Analysis of the Hipparcos data produces a well-determined astrometric orbit for the long-period system that has an inclination of 52{deg}. Our photometric observations show shallow primary and secondary eclipses of the short-period pair, and eclipse solutions result in an inclination of 81{deg}. Thus, the long- and short-period orbits are not coplanar. The mass of the unseen third component is 0.7M_{dot}_, corresponding to a mid-K dwarf. The total mass of the system, 3.08M_{dot}_, leads to a semimajor axis of 4AU for the outer orbit. The F5 V primary is rotating more slowly than it would if it were synchronously rotating, while the G8 V secondary may be synchronously rotating. The lithium abundance of the F5 V primary is similar to the initial lithium abundance found for Population I dwarfs and so indicates no significant dilution.
- ID:
- ivo://CDS.VizieR/J/ApJ/798/95
- Title:
- HE1104-1805 BVRIJ light curves
- Short Name:
- J/ApJ/798/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The gravitationally lensed quasar HE 1104-1805 has been observed at a variety of wavelengths ranging from the mid-infrared to X-ray for nearly 20yr. We combine flux ratios from the literature, including recent Chandra data, with new observations from the SMARTS telescope and Hubble Space Telescope, and use them to investigate the spatial structure of the central regions using a Bayesian Monte Carlo analysis of the microlensing variability. The wide wavelength coverage allows us to constrain not only the accretion disk half-light radius r_1/2_, but the power-law slope {xi} of the size-wavelength relation r_1/2_{prop.to}{lambda}^{xi}^. With a logarithmic prior on the source size, the (observed-frame) R-band half-light radius log (r_1/2_/cm) is 16.0_-0.4_^+0.3^, and the slope {xi} is 1.0_-0.56_^+0.30^. We put upper limits on the source size in soft (0.4-1.2 keV) and hard (1.2-8keV) X-ray bands, finding 95% upper limits on log (r_1/2_/cm) of 15.33 in both bands. A linear prior yields somewhat larger sizes, particularly in the X-ray bands. For comparison, the gravitational radius, using a black hole mass estimated using the H{beta} line, is log(r_g_/cm)=13.94. We find that the accretion disk is probably close to face-on, with cos(i)=1.0 being four times more likely than cos(i)=0.5. We also find probability distributions for the mean mass of the stars in the foreground lensing galaxy, the direction of the transverse peculiar velocity of the lens, and the position angle of the projected accretion disk's major axis (if not face-on).
- ID:
- ivo://CDS.VizieR/J/AJ/159/278
- Title:
- He-filter observations of WASP-69b & WASP-52b
- Short Name:
- J/AJ/159/278
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared observations of metastable 23S helium absorption with ground- and space-based spectroscopy are rapidly maturing, as this species is a unique probe of exoplanet atmospheres. Specifically, the transit depth in the triplet feature (with vacuum wavelengths near 1083.3nm) can be used to constrain the temperature and mass-loss rate of an exoplanet's upper atmosphere. Here, we present a new photometric technique to measure metastable 23S helium absorption using an ultranarrowband filter (FWHM 0.635nm) coupled to a beam-shaping diffuser installed in the Wide-field Infrared Camera on the 200inch Hale Telescope at Palomar Observatory. We use telluric OH lines and a helium arc lamp to characterize refractive effects through the filter and to confirm our understanding of the filter transmission profile. We benchmark our new technique by observing a transit of WASP-69b and detect an excess absorption of 0.498%{+/-}0.045% (11.1{sigma}), consistent with previous measurements after considering our bandpass. We then use this method to study the inflated gas giant WASP-52b and place a 95th percentile upper limit on excess absorption in our helium bandpass of 0.47%. Using an atmospheric escape model, we constrain the mass-loss rate for WASP-69b to be 5.25_-0.46_^+0.65^x10^-4^M_J_/Gyr (3.32_-0.56_^+0.67^x10^-3^M_J_/Gyr) at 7000K (12000K). Additionally, we set an upper limit on the mass-loss rate of WASP-52b at these temperatures of 2.1x10^-4^M_J_/Gyr (2.1x10^-3^M_J_/Gyr). These results show that ultranarrowband photometry can reliably quantify absorption in the metastable helium feature.
- ID:
- ivo://CDS.VizieR/J/ApJ/798/58
- Title:
- HELGA VI. Giant molecular cloud associations in M31
- Short Name:
- J/ApJ/798/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we present a catalog of giant molecular clouds (GMCs) in the Andromeda (M31) galaxy extracted from the Herschel Exploitation of Local Galaxy Andromeda (HELGA) data set. GMCs are identified from the Herschel maps using a hierarchical source extraction algorithm. We present the results of this new catalog and characterize the spatial distribution and spectral energy properties of its clouds based on the radial dust/gas properties found by Smith et al. (Paper II, 2012ApJ...756...40S). A total of 326 GMCs in the mass range 10^4^-10^7^M_{sun}_ are identified; their cumulative mass distribution is found to be proportional to M^-2.34^, in agreement with earlier studies. The GMCs appear to follow the same correlation of cloud mass to L_CO_ observed in the Milky Way. However, comparison between this catalog and interferometry studies also shows that the GMCs are substructured below the Herschel resolution limit, suggesting that we are observing associations of GMCs. Following Gordon et al. (2006ApJ...638L..87G), we study the spatial structure of M31 by splitting the observed structure into a set of spiral arms and offset rings. We fit radii of 10.3 and 15.5kpc to the two most prominent rings. We then fit a logarithmic spiral with a pitch angle of 8.9{deg} to the GMCs not associated with either ring. Last, we comment on the effects of deprojection on our results and investigate the effect different models for M31's inclination will have on the projection of an unperturbed spiral arm system.
